Fabrication and characterization of Fe/Ni nanoparticles supported by polystyrene resin for trichloroethylene degradation

In this study, Fe, Ni, and Fe/Ni nanoparticles were successfully incorporated in commercial polystyrene cation exchange resin, D072, to form Fe-D072, Ni-D072, and Fe/Ni-D072 composites. The resultant composites were characterized by scanning electron microscopy-energy dispersive spectrometer and X-ray diffraction. For the first time, the resultant composites were used to dechlorinate trichloroethylene (TCE), the target pollutant, in aqueous solution. The effects of initial concentration of TCE and solution pH on TCE removal efficiencies by Fe/Ni-D072 were investigated. The stability and durability of Fe/Ni-D072 were also examined. Results showed that Fe/Ni-D072 with 4% wt of Ni/Fe loading (mass ratio: Ni:Fe = 20:80) possesses superior dechlorination performance compared with TCE to Fe-D072 and Ni-D072. The freshly prepared Fe/Ni-D072 exhibited high reactivity during the dechlorination process of TCE. However, reactivity decreased with increased number of cycles. The leaching of Fe and Ni ions from Fe/Ni-D072 were approximately 0.2 ppm and less than 0.1 ppm, respectively, which are below the maximum acceptable level of Fe and Ni in water (0.3 mg/L for Fe and 0.1 mg/L for Ni) as suggested by the US Environment Protection Agency (EPA). The study confirmed that Fe/Ni-D072 is a potential catalyst to reduce environmental pollutants containing carbon halogen bonds such as TCE.